//class Base{
//    public int a = 20;
//    public int b = 90;
//}
//
//class Der extends Base{
//    public int a = 1;
//
//    public void method(){
//        System.out.println("a = " + a);
//        System.out.println("b = " + b);
//    }
//}

class Base{
    int a = 99;
}
class Der extends Base{
    //int a = 1;
    /*public void test() {
        System.out.println(super.a);//使用super关键字访问父类成员
        System.out.println(this.a);
        System.out.println(a);
    }*/
}

public class Test {
    public static void main(String[] args) {
        Der d = new Der();
        d.a = 99;
    }
}
